Purified fish oil concentrate. Commercial fish oils marketed as dietary supplements are typically derived from fresh, cold-water, oily fish, such as salmon, herring, mackerel, anchovies and sardines 1. The use of fish oil supplements is intended to provide the body with the essential omega-3 fatty acids, EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Concentrated fish oils tend to contain higher amounts of EPA and DHA. While consuming fatty fish can also provide these omega-3 fatty acids, most individuals do not consume the required servings. In addition, much of the available fish today is raised on farms rather than in their native water habitats, greatly reducing their concentrations of EPA and DHA. Furthermore, cold-water fish can contain dangerous amounts of environmental pollutants, such as mercury, PCBs (polychlorinated biphenyls) and dioxins 2. A major safety concern is the possible presence of these polluntants, which can be found in relatively high levels in fresh fish and unpurified fish oils. When considering omega-3 EPA and DHA dietary supplements, it is important to look for fish oils that have been purified to reduce the levels of these contaminants. The most common molecular distillation and steam deodorization techniques use a combination of pressure and high temperatures to remove environmental pollutants from fish oil supplements so that they may pass global regulatory standards 3.